This MHCRC emphasizes the study of schizophrenia and other major psychoses. Its unifying concept is the goal of linking the clinical presentation of illnesses with their underlying neurobiology. Specifically, most projects attempt to identify the neural or biological substrates that underlie abnormalities in mental phenomena. The CRC consists of four core units and six research units. The Administrative Core is responsible for maintaining centralized records of all protocols, managing a five bed inpatient research unit, and coordinating the efforts of investigators between themselves and with the institution as a whole. The Assessment and Training Core maintains a core assessment battery, provides a training and calibration program for the various instruments used in CRC protocols, conducts studies of reliability, and develops new assessment techniques. The Biostatistics Core provides biostatistical consulting and collaboration to investigators at all stages of the research effort and maintains a computer system; it also maintains a centralized core data base and provides quality assurance at all levels of core data processing. The Image Analysis Core provides a centralized resource for the analysis of imaging data, including the development of new software techniques, training on the use of workstations, and a quality assurance program. The Diagnosis and Phenomenology Research Unit examines clinical issues, including cross sectional description, dimensional versus Categorical approaches, comparative nosology, and longitudinal course. The MR Unit focuses on structural brain abnormalities and explores various aspects of brain anatomy in relation to a variety of disease processes, including schizophrenia, autism, and eating disorders; this unit also examines gender differences in brain structure. The PET unit emphasizes the use of 150 water technique in order to explore cognitive systems in normal individuals (i.e., attention, memory, language, and mood) in normal individuals and in various disease processes, including mood disorders and schizophrenia. The Cognitive Neuroscience Unit uses the techniques of experimental cognitive psychology and neuropsychology to focus on the relationship between cognitive systems and disease processes. The Genetics Unit takes a comprehensive approach to studying the genetics of major psychoses, using twin studies, multiplex family studies, and molecular genetics. Specific projects also target epidemiological factors, such as exposure to toxins or viruses. The Neuropharmacology Unit pursues the study of pharmacokinetics, drug dosage, target symptoms, and side effects.